Answer:
y = 67.6 feet, y = 114.4/ (22 - 3t)
Explanation:
For this exercise let's use that light travels in a straight line and some trigonometric relationships, the symbols are in the attached diagram
Large triangle Projector up to the screen
tan θ = y / L
For the small triangle. Projector up to the person
tan θ = y₀ / (L-d)
The angle is the same, so we equate the two equations
y₀ / (L -d) = y / L
y = y₀ L / (L-d)
The distance from the screen (d), we look for it with kinematics
v = d / t
d = v t
we replace
y = y₀ L / (L - v t)
y = 5.2 22 / (22 - 3 t)
y = 114.4 (22 - 3t)⁻¹
This is the equation of the shadow height change as a function of time
For the suggested distance the shadow has a height of
y = 114.4 / (22-13)
y = 67.6 feet
Answer:
9.01amp
Explanation:
Power = V^2/R
Given that v = 11volts, P = 99watts
99 = 11^2/R
11×11 = 99R
121= 99R
R = 121/99
R= 1.22ohms
From ohms Law; V = IR
11volts = I × 1.22ohms
I = 11/1.23
I = 9.01 amp
Answer:
60000 J
Explanation:
Assuming the force is applied parallel to the displacement of the elephant, the work done to move it across the floor is
where
F = 2000 N is the force applied
d = 30 m is the displacement of the elephant
Substituting the numbers into the formula, we find
Explanation:
Given that,
Frequency of the power line, f = 6 Hz
Value of maximum electric field strength of 11.6 kV/m
(a) The wavelength of this very low frequency electromagnetic wave is given by using relation as :
(b) As its can be seen that the wavelength of this wave is very high. It shows that it is a radio wave.
(c) The relation between the maximum magnetic field strength and maximum electric field strength is given by :
So, the maximum magnetic field strength is 
.
